Is this any better?

#!/usr/bin/perl

use strict;
use warnings;

my @AUBBC_TAGS = (
    'b',  'i',     'sub', 'sup', 'pre', 'ul',
    'ol', 'small', 'big', 'li',  'p',   'h1',
    'h2', 'h3',    'h4',  'h5',  'h6',  'div',
    'strong'
);

my $message = '[b] stuff [i] stuff [/i] [/b]';
foreach (@AUBBC_TAGS) {
    $message =~ s/\[(.?)?$_\]/<$1$_>/gx;
}
print $message, "\n";
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